The 3" Spokane PD example shown above reminded me of a situation in my hometown, Columbia, MO, in the early 1970's. About that time they got a new Chief of Police and he was big on modernizing the department. One of his efforts was to switch from 4" M15s to 6" M28s for patrol officers....
Well, at that time there was one female officer paying her dues on patrol duty before being moved into the detective ranks to deal with crimes against women and children. It seems this lady was so petite that she couldn't reasonably wear a M28 6" in a patrol car even though she could shoot it just fine. So she was outfitted with a 3" M36 for her tour of duty as a patrol officer until the brass could justify moving her into investigations. That Spokane PD 3" would have been about the same vintage as the one they issued her.